Musnad Ahmad 30:2941

'Abd al-Malik ibn 'Amr narrated to us, he said: Ibn Abi Dhi'b narrated to us, from al-Zuhri, from 'Umar ibn 'Abd al-'Aziz, from Ibn Qariẓ, from Abu Hurayrah, that the Prophet, peace and blessings of Allah be upon him, said: "Perform ablution from what the fire has touched."